Embodiments of the present invention relate to image processing technology.
Electronic devices including a display unit display video data together with graphic data for UI including on-screen display (OSD) data. OSD may provide information on the video data or show whether functions are executed in response to a user's operation. Users may be sensitive to the quality of video data displayed on a screen but may not be sensitive to the quality of graphic data. Accordingly, when the graphic data is compressed to be stored in a memory and decompressed to be displayed on the screen, the bandwidth of the memory that stores and outputs the graphic data may be reduced.
When graphic data is compressed using a conventional method such as a video coding layer (VCL), it may be difficult to realize lossless compression and maintain a compression ratio constant. Moreover, combining UI and video data using chroma key may not be carried out by conventional scalers.